Process of improving oils.



A. MOD. MGAFEE.

PROCESS OF IMPROVING OILS.

APPLICATION FILED 1113.12, 1914.

1,127,465, Patented Feb.9, 1915.

ALMER MQDUFFIE MCAFEE, OF BAYONNE, NEW JERSEY.

rnocnss or IMPROVING OILS.

menace.

Specification of Letters Patent.

Patented Feb. a, rare.

Application filed February 12-, 1914. Serial No. 818,286. r

To all whom it may concern Be it known that l, IALMER.MCDUF F1E MCAFEE, a citizen of the United States, re

A siding at Bayonne, in the county of Hudson and ,State of New Jersey, have invented certain new and useful Improvements in Processes of Improving Oils, of which the following is a specification.

lhis invention relates to processes of improving oils; and it comprises a method of treating petroleum oils to secure greater quantities of distillates of better quality than are given by the usual practice and to secure a better quality of residual oil; and,

more speeifically'stated, it comprises a pro-' cess wherein petroleum oils are heated in the presence of aluminum chlorid in such a manner as to secure a catalytic conversion of a portion of the higher boiling oils into lovver boiling oils, such lower boiling oils being distilled off and removed, and to conreit the residual oil into a better grade of material than is obtained by present processes; such process being particularly applicable to the improvement of crude petroleum; all as more fully hereinafter set forth and as claimed.

- The crude petroleums from the various oil-producing districts differ materially in quality and constitution. Some of these oils, like Pennsylvania oil and Caddo (Louisiana) oil, are largely of a paraflin gen.

. ing.

nature; "that; is, they are neutral bodies which do not oxidize readily, are clean and require but little acid in refinhers of these oils, like Mexican crude and some of the Texas crudes, contain large amounts of asphaltic bodies, and their distillation products are not of high smelling grade, tending to oxidize and gum on exposure to air. Other'oils, like certain Oklahoma crudes, are of an mterrnediatenature containing both parafiin andjas'phalt. Many of. these oils, like the Texas and Mexican crud'es, contain large amounts of, sulfur.

- In the ordinary process of of these crudes the gasolene (if any-he prescut) and the kerosene (if any be'pne sent) 'naturallybontained therein are first distilled-01f... 'QThe residual on, remaining in i the still after the naturally occurring asolene and: kerosene have been remove, is worked up into a variety of product's,fdepending upon the character of the particular crudes and upon market oonditions In .Caddo oils, I obtain a substantial some cases with some of these crudes, the whole of this residual oil is marketed as Ind 011, no attempt being made to utilize it for higher grade products. In other cases the residual oil is itself distille further to produce lubricating stocks and cylinder oils in fire-heated stills 'with the aid of steam introduced into the oil body; by what is usually termed' bottom .steam distillation. Except in the case of asphaltic oils, if the residual oils contain substantial amountsof paraffin, they may be subjected to the so- 1 called cracking process whereby the parafin is caused to become crystalline, whichis I generally necessary in separation of parafii'n wax from oil by pressing. A relatively small amount of, gasolene and burning oils is produced and recovered from high boiling hydrocarbons during this cracking operation, butthe quality of these products is poor on account of their highly unsaturated nature, and the lubricating values of the paraffin oils are considerably impaired.

\Vith all these oils, the residual materials after-distilling off the naturally occurring gasolenes, or gasolene and burning oils, are susceptible of improvement by the process hereinafter set forth. While the residues from Pennsylvania and Caddo crudes, and

ment. 1

In my process, I heat these crude oils with aluminum-'chlorid to improve their character; and by a proper use ofthis chemical I find'tI can not only obtain high-boiling 1 105 -a large yield of -what I may term, for the oils of much better quality but also obtain sake of a name, secondary distillates of high grade. The action oftheialuminumchlofld is, in part, to produce or form low-boiling bodies like gasolene {and by proper manipu lation in "the present process L'can form a secondary distlllate of gasole'ne or of 'gaso;

lene,'solvent oils (commercially often called I turpentine substitutes l) and kerosene.

asphaltic bodies to disappear.

Such asecondary distillate is water white, sweet, and substantially saturated, and is not like the cracked gasolenes or" cracked distillates frequently made by destructively distilling residual high boiling oils after re moval of the primary distillate of naturally contained gasolene, or gasolene, solvent oils and burning oils. And this secondary distillate consisting of high grade gasolene I can produce from oils which naturally contain no gasoleneythat is oils which do not yield a primary gasolene upon simple distillation. For example, on heating a low grade asphaltic crude, like Sour Lake (Texas) crude containing no primary or natural gasolene with aluminum chlorid, I secure a good yield of high-grade gasolene and burning oils, while from the high-boiling 'residual materials, I may obtain pale lubricating oils and cylinder oil, both free of asphaltic constituents.

Many crude oils which normally cannot be used to produce paraflin (like some Oklahoma crudes) can be transformed into oils useful for this purpose. Some Oklahoma crudes contain both paraflin and asphalt but owing to the presence of the latter the former cannot be obtained by the usual methods. On treatment with aluminum chlorid, the asphalt and asphalt yielding hydrocarbons of the oil are converted into other bodies, probably, to a large extent at least, by conversion into lighter oils, and the oil under treatment loses much of its vis-' a little aluminum chlorid, I can convert Mexican crude into a fuel oil low in sulfur and meetlng exacting specifications in this respect as Well as-in regard to viscosity.

- In all cases prior to using aluminum chlorid I first heat the oil to dry it and, in case gasolene is naturally contained, to recover it as a primary distillate. I then add my aluminum chlorid in such quantity as may seem expedient with the particular oil used and for the purpose intended and heat for a time long enough to convert the unsaturated bodies into saturated and to cause This causes also the formation of a relatively large amount of secondary gasolene of high grade, and this I generally remove and re-,

cover. Often, since I'am; here seeking to purify and stabilize heavy oils I adjust heat-' ing conditions, time of treatment, quantity of aluminum chlorid, etc., so as to leave about 30 to 50 per cent. of oil (calculated on the amount of crude oil used) in the still when the removal of newly formed light oils is completed; but this proportion may vary. But generally there is at; least a substantial quantity of heavy .oilremaining. This I may remove from the still and treat with I sulfuric acid prior to performing the usual operations for the manufacture of lubricating oil andwaX-bearing distillate, orcyl inder oil, as the case may" be. The sulfuric acid treatment s more for the purposeof removing traces of aluminum chlorid than for the ordinary purpose of removing unsaturated bodies. I may use a half or third the quantity of acid ordinarily employed in treating oils. Of course otherways .of removing residual aluminum chlo-' groups constituting the hydrocarbon mole cules with conversion of unstable into chemically stable bodies. In this rearrangement f-there is usually, at high temperatures, a formation of secondary long-boiling oils and these are of course worth recovering. In the presentinvention I do not carry the conversion so far as to convert all, or substan tially all, of my oil into gasolene and the like but conduct the operation in such a l way as to leave a substantial proportion of high-boiling oils, the amount remaining being often around 30 to 50 per cent.

While a treatment of oil with aluminum chlorid at high temperatures leads to the production of low boiling bodies at the expense'of high-boiling, at low temperatures,

say around 150 F., the conversion does not go so far; a fact which may be utilized in the purification and decolorizing of lubricating oils. Such oils in so treating while undergoing profound internal changes of beneficial character do not furnish any material amount of low boiling oils. In the present invention While- I utilize the beneficial effect of aluminum chlorid upon the character of high boiling oils, I go somewhat further and by operating at higher temperatures also produce a proportionof low-boiling as a by product oils.

As a rule, in producing my secondary volatile products, I prefer to make mainly gasolene, although this is a matter of market conditions, and I may at times produce gasolene, burning oils and the grade known as solvents. While gasolene is always produ'ced, the particular character of the secondary products made depends mainly upon the temperature at which such secondary products are allowed to escape from the densable at 300 .F. the product will be mainly gasolene; where higher-boiling materials are allowed to gopast the condenser, I may obtain much of the other volatile bodies.

The amount of aluminum chlorid employed depends upon the particular results sought. Where I wish mainly to improve the quality of the residual oil .I need use only a small amount, say 1 to 3 per cent; if I amseeking also a large production of A gasolene, it is generally better to increase the proportion somewhat, say to 5 per cent. The aluminum chlorid employed may be made in any convenient way, as by treating aluminum, or alumina and carbon, with chlorin or hydrochloric acid. Aluminum chlorid may be recovered from the residues after treating oil by heating such residues to carbonize them and passing into contact therewith a small amount of chlorin or hydrochloric acid. Somewhat heightened results may be obtained by using in lieu of aluminum chlorid an addition of finely divided metallic aluminum to the oil, and passing chlorin into the oil. tions of aluminum chlorid stated are, however, only indicative; the amount employed must always vary with the particular oil and with the particular purpose for which my processis employed. It will also vary with the way in which the process is conducted. F or example, instead of using about 5 per cent., which is generally a suit-v able quantityI may add 10 per cent. of aluminumchlorid to a charge of oil and heat therewith until the delivery of gasolene beyond the condenser begins to di- "minish or, until the development of the gasolene vapors lessen. At this time, I may cool the oil to allow the aluminum chlorid to deposit, removing the cooled oil for further treatment elsewhere, and then add another like charge of dry oil to the aluminum chlorid remaining in the still. Here although I have added 10 per cent. in

the beginning I am virtually using only 5 perfcent. for a single-charge. The aluminum chlorid may of course be added portionwise; that is instead of adding 5 per I cent. at once, this amount may be added in 'There is two or three or more portions. however-little advantage in this.

The oil temperature in the operation is generally at the boiling point; around 500 F. Where I am making a large proportion of gasolene, the oil may be at any temperature from 500 to 600 F.', but is generally around 500 F., while I hold the temperatures of the vapor allowed to leave the vapor line of the still at not above 300 to 350 F.

The time of treatment varies with the specific results sought. Ordinarily I beat The proper.

of the vapor at which distillation began) of 307 F. 10 per cent. distilling over below 481 and &4 per cent. below 6009, the temperature at which cracking began. A charge of'the Texas crude was'first heated in still to get rid of water. At the time when the temperature in the vapor line at the point of entrance to the condenser showed 350 F., I deemed the oil free of water. There was a distillate (3.57 per cent.) which was of the character of burnin}; oil. I then added 5 per cent. by weight of aluminum chlorid (on the weight of oil" remaining in the still) and continued the heating, adjusting conditions so that the vapor temperature at the point stated remained around 350. There was a formation of secondary distillate and'at the end of 4:8 hours the flow from the condenser slackened owing to the aluminum chlorid becommg less active.

The secondary distillate obtained amounted to 48.81 per cent. of the original crude oil. l/Vith the apparatus and under the-conditions which I used in this 'particular operation, I sent over into this original crude oil) 24.40 per cent. gasolene,

12.15 per cent. solvent oils and 12.26 per cent. burning oils. All were waterwhite, clean-smelling and required no acid or other purifying treatment to finish them for their respective uses.

.'Returning now to the residual oil remaining in the still at the end of the described distillation, this oil amounted to 33.33 per cent. of the original crude oil. It was cooled and drawn off, leaving a granularcoky sludge containing aluminum chlorid. This sludge was then treated to regain adhering oil and recover aluminum chlorid. The withdrawn oil was treated with fuming sulfuric acid to remove any dissolved aluminum chlorid,

using the acid in about the proportion of 12 of 285; a. fire test of 360; and a viscosity -ple showed an over-point (the temperature stock.

(Saybolt Universal viscosimeter) of 177 at 100 F. It was worked up into pale lubricating oils of excellent quality and cylinder There was no tar. This crude oil is one which is not ordinarily employed for making burning oils. It contained no gasolene. The one'low-boiling distillate usually made from it is solvent oil. .To make this oil it is-steam distilled with bottom steam in the ordinary way. About 80 per cent. of oil remains in the still at the time when this solvent oil has gone over. The solvent oil, unlike the volatile oils obtained in the presentLinvention from the same material, required refining with acid. The 80 per cent. remaining in the still by the usual process is black, acrid-sinelling and highly unsaturated. When the distillation is continued beyond this point there are produced gas oil, lubricating stocks and residual tar from which asphalt is made. The gas oil is a relatively low priced material and the tar has little value. The lubricating stocks are of low grade and require a treatment with at least 20 or 30 pounds of sulfuric acid per barrel, followed by an alkali wash and fullers earth treatment to make them of a I I obtain 35.7 barrels of primary distillate (kerosene); 244 barrels of gasolene;- 121.5 barrels of solvent oils; 122.6 barrels of burning oils; 155 barrels solar oil; 62 barrels pale lubricating oil; and 93 barrels of cylinder stock all of high grade. The loss on this basis would be 166.2 barrels as gas, coke,"

and in acid treatment.

In treating a Mexican crude oil, containing both asphalt and paraflin, and conta n:

ing sulfur in large amount together with nitrogen, I first distilled to remove water and'a primary distillate. ThlS primary dlstillate amounted to 10.72 per cent., mostly gasolene. I then added 5 per cent. of aluminum chlorid and continued the heating. I now obtained 25 per cent. of secondary distillate half of which was gasolene. In spite of the low quality of the original crude oil, the gasolene from this secondary distillate was clean smelling,.water white and needed no treatment with acid. The residual high boiling oil after separating the aluminium chlorid amounted to 40 per cent. of the original crude. It was greenish and free from asphaltic constituents. The flash point was 310F. and the pour or cold test (the point at which the liquid becomes too viscous to pour) was 55 F. This residual oil I worked up into Wax stock and cylinder oil.

Both were of good quality in spite of the presence of asphalt and a large amount of sulfur in the original crude oil.

With a Caddo oil, which I treated to obtain a stock of the nature of that commer cially known as Vaseline stock, I first distilled to free it of water and obtained a primary distillate. amounted to 26.19 per cent. I then added 5 per cent. of aluminum chlorid and continued the heating. per cent. of secondarydistillate, about half of which was gasolene. In this operation, I pushed the manufacture of secondary distillate to a point where I had left in the still 18.7 per cent. of residual oil. This residual oil after the aluminum chlorid had been separated, was a light pale oil of 260 F. flash and a pour test of 90 F. This material was worked up into Vaseline by distil- I now'obtained 41.67

The primary distillate ling with bottom steam until 30 per cent. of

"light lubricating oil had passed over. The

residue was light-colored material which only needed filtration with fullers earth to give a high grade Vaseline-like product. I obtained 13.1 per cent, calculated on the crude, of commercial Vaseline.

With an Oklahoma crude containing both paraffin and asphalt which Itreated to obtain a relatively large quantity of secondary gasolene, I obtained 20.83 per cent. of primary distillate in heating till a thermometer inthe vapor line recorded 350 F. Of this 14.58 per cent. (on the crude) was gasolene. On now adding 5 per cent. aluminum chlorid, I obtained 50.60 per cent. of secondary distillate. In this operation I wished to make a large quantity of secondary distillate of gasolene and burning oils. On redistillation I obtained 21.50 per cent. (on the crude) of high-grade gasolene. Inthe still at the time I discontinued distilling for secondary products, I- left 14.07 per cent. (on the crude) residual oil. This, after treatment with sulfuric acid, had a pale color with green bloom; a flash point of.

300 F. and a pour test of F. This material-was worked up into wax stock and cylinder oil, the yield of the latter being 5.24 percent. (on the crude), with a greencolor, fire test of 615 F. and a pour test of 30 F. Although the crude oil contained asphalt, no tar was made and from the wax stock, treated in the usual ways, I secured good white parafiin wax.

In the work recorded in the foregoing exemplificatory operations, I used conditions such as gave me burning oils and solvent oils as well as gasolene. In similar work how ever on the same oils where I desired to increase the amount of gasolene in the secondary distillate, I secured this result by simple refluxing back the burning oil and solvent as 16. 'Themanhole 25 ma y. beprovi-ded-instead.

mamas way dependent on any particular type of apparatus, and indeed may be performed in any of the usual stills, I have shown more 01' less diagrammatically, an apparatus of a type I have used with advantage in the conversion of oils with production of secondary gasolen'e. In this showing the figure is acentral vertical section (partly in elevation) of a single still and accessory parts.

Element 1 designates the still proper, as a whole. Oil may be introduced through a valved inlet 2 and withdrawn through a valved outlet 3. Firing meansare diagrammatically shown at 4. At the top, the still is provided'with the top 5, carrying stirring means 6. In a small sized still the whole top-may be removable. Passing through the cover is a vapor outlet 7 leading to the chamber 8. The vapor line 9 leads from this chamber to an air cooled condensing chamber 10. As shown, this is of simple cylindrical design; but any other type of air cooled condenser may be substituted in its From this condensing chamber a vapor conduit 11 leads to another and similar condensing chamber 12. Beyond this chamber is a vapor conduit 13 carrying a thermometer 14 and provided with a valve 15.- Beyond the valve this conduit connects with a condenser or cooling device 16, shown diagrammatically as a series of connected pipes in a tank 17 adapted to hold water or other cooling fluid. At the base of the first air condensing chamber is an outlet 18 connected to a reflux conduit 19. As shown, this reflux conduit hasa portion 20 at a lower level to serve as an "oil trap. Connected to this reflux conduit is an outlet 21 for the second air cooled condensing chamber. The valve 22 allows communication between the outlet and the reflux conduit to be closed or opened at pleasure. Connected to element 21- above this valve is avalved outlet conduit 23 leading to a cooler 24 shown aslocated in the .same' cooling tank N the top of thestill for introducing alumi;

num chlorid and for other purposes. In

the use of this structure, a suitable charge of crude oil may be introduced through the inlet 2 and heated until the thermometer 14 shows a vapor temperature between 300 F. and 350 F. At this time the oil is free of Aluminum chlorid in the desired amountmay now be introduced through the manhole 2'5 and the heating continued. An evolution of vapors, of low boiling oils at once begins and passes upward past the chamber 8 through the conduit 9 into the condenser 10. The chamber 8 serves to retain' and return any aluminum compounds,

etc., that may be carried up mechanically or otherwise. In the condensing chamber 10 "vapors are more or less cooled andv such oil as condenses passes downward through 18 distillation.

into 19, and back to the still, the-depression 20 serving as an oil trap. Uncondensed vapors go forward through 11 into'the conplace. The valve 23 being closed and the valve 22 open, the condensate formed in this chamber returnsor refluxes through the, trap 20 and conduit 19 to the still. With the thermometer 14 standing at 300 F. to 350 two cuts in this manner, the gasolene condensed in element 16 needs no further re- The product collected from the cooler 24 will be solvent and burning oils or either according to the temperature in the condenser 12.

lVhile for the sake of simplicity of illustration I have shown but two air-cooled condensers used in series and have shown means for collecting but two cuts and have shown these elements as of a simple type, it will be obvious that any number of condensers may be used in series and that they may be 0t any type. The condensers may be cooled'in any other way in lieu of being simply air cooled as shown.

' duit 12 where a further condensation takes In using the above described apparatus,

after charging the oil, heat may be applied till the flow of condensate from condenser 16 slackens. Aluminum chlori'dmay I be added in the desired amount and heating continued. A new flow begins and'when this I slackens, firing may be interrupted and the residual oil cooled and removed. 7

The expulsi-onof Water'an'd primary distillate may of course be efi'ected in one still and the hot dryoil transferred to another still for treatment with aluminum chlorid if it is desired,

What 'I claim is f 1. In the improvement of oils the process which comprises heatinga high-boiling 011 with aluminum chlorid. while distilling ofl low boiling oils formed, cooling the heated oil at a time when a substantial amount of high boiling oil still remains and separating the aluminum chlorid from the high boiling oil. I

In the improvement of crude petroleum, the process which comprises heat ng a crude petroleum to remove low boiling oils and moisture, adding aluminum chlorid,

heating with removal of low boiling oils formed during such heating, cooling the petroleum at a time when a substantial amount of high boiling oil still remains and separating the aluminum chlorid and the high boiling oil.

3. The process of improving crude asphaltic petroleum which comprises distilling the same with aluminum chlorid until a portion of the high boiling oils is converted into saturated compounds and freed of asphaltic constituents, said low boiling oils being removed as fast as formed and the heating operation being interrupted while a substantial portion of the high boiling oil so freed of asphalt still remains.

- 4. In the improvement of crude petroleum, the process which comprises heating a crude petroleum to remove 'low boiling oils and moisture, adding aluminum chlorid and distilling off the low boiling oils produced thereby till a substantial proportion but not all of the high. boiling oil has been converted oil at least 30 per cent. of the original oil still remains, cooling this remaining oiland separating oil and aluminum chlorid,

6. In the improvement of crude petroleum the process which COIIPIISBS freeing a crude petroleum of moisture and-primary gasolene,

adding aluminum'chlorid and heating to form and remove secondary gasolene, cooling residual oil while a substantial amountstill remains and separating 011 and ZllLlIllI- num chlorid. g 7. Inth'e manufacture of secondary gasolene by heating .a body of high boiling oils with aluminum chlorid, the process of nianufacturing high grade lubricating oils which comprises interrupting said heating while a substantial quantity of high boiling residualoil remains, cooling the residual oil and separating aluminum chlorid and refining the residual oil to produce high grade lubricants.

8. In the improvement of petroleum oils,

I the process whichcomprises distilling such an oil with aluminum chlorid, cooling the residual oil-and finally removing dissolved aluminum chlorid by treatm'ent with sulfuric acid. c

9. In the, improvement of petroleum oils, theprocess which comprises heating such an oil to a temperature below 600 F. in

the .presence of aluminum chlorid, inter- "rupting the heating while a Y. substantial quantity of liquid oil at this temperature still remains, cooling and finally removing dissolved aluminum chlorid by treatment with sulfuric acid. y

10. In the improvement of petroleum oils, the process which comprises heating such an oil to a temperature below 600 F. in the presence of aluminum chlorid, interrupting the heating while a substantial quantity of liquid oil at this temperature still remains, cooling and separating oil and aluminum chlorid.

11. In" the improvement of petroleum oils the-process which comprises heating crude petroleum oil till the evolution of vapors.

.mary gasolene, adding aluminum chlorid, distilling off secondary gasolene, cooling.

residual oil and separating oil and aluminumchloridr 14:. In thetreatment of petroleum oils the process which comprises heating such an oil with aluminum chlorid for 36 to 48 hours while removing vapors of secondary gasolene, cooling and separating oil and aluminum chlorid.

15. In the improvement of petroleum oils the, process which comprises heating the same with aluminum chlorid while constantly removing vapors at a temperature not above 350 F., such heating being interrupted at a time'when asubstantial amount of high boiling oil stillrema-ins and such high boiling'oil being cooled, and separating the aluminum chlorid and cooled oil. 4 4

16. In the improvement of petroleum oils the process which comprises heating such an oil with aluminum chlorid while removing vapors at a temperature not above 350 F., vapors condensing above this temperature being condensed and refluxed back, cooling the oil at a time when a substantial amountofhighboiling oil still remains, and separating the oil and aluminum chlorid.

In testimony whereof, I affix-my signature in the presence of two subscribing witnesses.

ALMER MODUFFIE McAFEE.

Witnesses: i F. K. HAUXHURST,

JULIA M. MCCABE.

It is hereby certified, that in Letters Patent No. 1,127,465, granted February 9,

1915, upon the application of Almer McDufiie McAfee, of Bayonne,New Jersey, I

v for an improvement in Processes of Improving Oils, errors appear. in th i t d speeification requiring correction as follows: Page 2, line '83, for the word of read 07'; same page, line 120 after the compound word low-boiling insert'the word oils and same line after the word product strike out the word oils; page 3, line 42, for the word lessen read lessens," page 6, first-mentioned witness to the signature of the patentee, for .F. K. Hauxhurst read T. S. K. Hams/aunt; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the ease in the Patent Ofiice.

Signed and sealed thisf13th day of April, D 1915.

[SEAL-1 J. L. NEWTON,

Acting Commissioner of Patents 

